[1] Univ Hosp Ulm, Gynecol & Obstet, Ulm, Germany
[2] Klinikum Ludwig Maximilians Univ, Gynecol & Obstet, Munich, Germany
[3] Univ Hosp Erlangen, Gynecol & Obstet, Erlangen, Germany
[4] Univ Tubingen Hosp, Gynecol & Obstet, Tubingen, Germany
[5] Univ Heidelberg Hosp, Ulm, Germany
[6] Univ Hosp Hamburg Eppendorf, Gynecol & Obstet, Hamburg, Germany
[7] Univ Hosp Essen, Gynecol & Obstet, Essen, Germany
[8] Univ Hosp Hamburg Eppendorf, Hamburg, Germany
[9] Heinrich Heine Univ, Gynecol & Obstet, Dusseldorf, Germany
[10] Univ Hosp Dresden, Gynecol & Obstet, Dresden, Germany